dare4liberty's Journal, 18 March 2011

How to Calculate Your Protein Needs:

1. Weight in pounds divided by 2.2 = weight in kg
2. Weight in kg x 0.8-1.8 gm/kg = protein gm.

Use a lower number if you are in good health and are sedentary (i.e., 0.8). Use a higher number (between 1 and 1.8) if you are under stress, are pregnant, are recovering from an illness, or if you are involved in consistent and intense weight or endurance training...



Calculating Protein as a Percentage of Total Calories

Another way to calculate how much protein you need is by using daily calorie intake and the percentage of calories that will come from protein. To do this, you'll need to know how many calories your body needs each day.

First, find out what your Basal Metabolic Rate is by using a BMR calculator.

Next, figure out how many calories you burn through daily activity and add that number to your BMR. This gives you an estimate of how many calories you need to maintain your current weight.

After you've figured out your maintenance calories, next figure out what percentage of your diet will come from protein. The percentage you choose will be based on your goals, fitness level, age, body type and metabolic rate. Most experts recommend that your protein intake be somewhere between 15 and 30%. When you've determined your desired percentage of protein, multiply that percentage by the total number of calories for the day.

http://exercise.about.com/cs/nutrition/a/protein_2.htm